At least 618,000 Americans died in Civil War and some say the toll reached 700,000. At any rate, these casualities exceeded the nation's loss in all its other wars, from the Revolution through Korea. Out of approx. 2,750,000 men, the Union army lost 110,070 in battle and 250,152 to disease. The Confederates had approx. 1,250,000 men, of which 94,000 died in battle and 164,000 died of disease. These numbers are handicaped due to poor records in some cases.

Thank you originalbinks.

The total amount has been estimated at between 600,000 and 640,000 killed, wounded and missing. This is the most costliest war in american history.